Marco Musacchio

Marco MusacchioI study active matter through experiments and simulations, with a nod to theory.

PhD student in theoretical physics
Institute for Theoretical Physics II – Soft Matter, Heinrich-Heine University Düsseldorf

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Orderφ = 0.00
disordered gas

Move your mouse over the particles and they flee; click for a shock wave. The noise η takes the system from an ordered flock to a disordered gas.

Portrait of Marco Musacchio

I study active matter: systems made of units that consume energy to move by themselves, from flocks to bacteria to small robots.

I am a PhD student at the Institute for Theoretical Physics II – Soft Matter of Heinrich-Heine University Düsseldorf, in the group of Hartmut Löwen. I work on non-equilibrium physics and active matter. Before that I studied at La Sapienza University of Rome, with a Bachelor in Physics and a Master in Biophysics.

What I work on

All projects
  1. Experimental setup and analysis. Top: robots moving around, viewed from above, with white dots indicating their direction of motion. In the right panel, particles are coloured according to their speed: fast (hot) particles are red, while slow (cold) particles are blue. The snapshot shows the coexistence of a cold cluster within a hot particle environment. Bottom: side view of the robots.
    2024-2025

    Frictional cooling in active matter

    We have identified a spontaneous cooling phenomenon in active matter, termed self-sustained frictional cooling, arising from the interplay between activity and dry friction, without the need for an external thermal bath. Through experiments and simulations on active granular robots, we demonstrate how this mechanism can lead to the formation of dense, arrested clusters, opening new perspectives for controlling the dynamical and structural properties of robotic swarms.

  2. Chiral mini-robots (black disks) follow circular trajectories (grey curved paths), exerting pressure on the system boundaries. This generates an increase in the effective temperature and induces edge currents (blue arrows).
    2025-2026

    Thermodynamics of chiral particles

    We developed a thermodynamic framework for chiral active matter, establishing an equation of state that connects the microscopic properties of rotating active particles to macroscopic quantities such as pressure and temperature. Our findings provide new insights into the collective behaviour of chiral active systems, paving the way for the design and control of autonomous active machines and microfluidic devices.

  3. Schematic representation of the self-aligning torque acting on an active particle. The torque, proportional to the cross product of the particle's orientation vector and velocity, tends to align the particle's orientation with its direction of motion.
    2024 - oggi

    Self-aligning active particles

    In active matter systems, the self-alignment mechanism, which aligns the particle orientation with its instantaneous velocity, can profoundly affect collective behaviour. At high densities, sufficiently strong self-alignment suppresses MIPS and induces a transition from a disordered state to a homogeneous flocking state, even in crystalline configurations. In the latter case, the transition can be analytically described within a Landau–Ginzburg theory. The introduction of chirality further enriches the phase diagram, favouring the formation of rotating crystals (circling crystals) and, at higher chirality, vortex-like structures.

  4. Schematic of active robots exhibiting magnetic interactions.
    2024-2026

    Magnetic active matter

    Magnetic active matter investigates out-of-equilibrium systems in which magnetic interactions combine with particle self-propulsion, giving rise to novel collective phenomena and forms of self-organisation. These interactions can profoundly influence system dynamics, modifying clustering processes, structure formation, and transport properties. Studying these systems through experiments and simulations provides insights into how magnetic interactions shape the collective behaviour of active matter across different length scales.

Recent publications

Full list

Get in touch

marco.musacchio00@gmail.com